With development of terminal technologies, a growing number of portable devices for personal computation have emerged, such as smart phone, notebook, and the like. These lightweight personal computing devices use a rechargeable battery to provide power for a time period. Due to size limitation, the provided rechargeable battery may be unable to supply enough power to meet the power requirements in a portable state. If the battery has been used up, and a user cannot charge the battery in time, the portable device cannot work, and its portability is degraded.
In view of the problem, a device capable of supplying power to the portable device has been introduced to the market. Currently, there are mainly two types of the device.
The first type of the device is a battery extension dock of a notebook computer. Coupling an extension dock to the notebook computer equals to coupling a second battery to the notebook computer. The battery in the extension dock can supply power only to the notebook computer. The notebook computer can obtain the status information of the battery in the extension dock, but cannot use the battery to charge the battery installed in the notebook computer. Thus, the user has to carry the extension dock in addition to the notebook computer, in order to use the power in the extension dock. This is inconvenient for the user.
The second type of the device is an external battery charger for mobile phone and the like. The battery charger is coupled to the mobile phone. That is, a charger is coupled to the mobile phone, and the electric power stored in the battery of the external battery charger can be used to charge the battery installed in the mobile phone. However, there is a problem that the mobile phone cannot obtain status information of the battery in the external battery charger, such as remaining power level, temperature, and voltage. Further, there is no power supply strategy, and the battery in the mobile phone will be changed as soon as the external battery charger is coupled. Such charging process causes loss in electric power.
During research and practice of the conventional schemes, the inventor has found that although the conventional schemes, either the extension dock or the external battery charger, can supply power to the notebook computer, the extension dock cannot be used to charge the computer's battery, and thus the user has to additionally carry the extension dock when going out. This causes inconvenience to the user. Although the external battery charger can charge the battery of the mobile phone, the mobile phone cannot obtain status information of the battery in the external battery charger, which will compromise convenience for the user.